{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"PCF8574ADWG4","brand":"Texas Instruments","brandSlug":"texas-instruments","productSlug":"PCF8574ADWG4","canonicalUrl":"https://icboms.com/texas-instruments/PCF8574ADWG4","factsUrl":"https://icboms.com/api/mcp/products/PCF8574ADWG4","rawCanonicalId":null},"summary":{"shortDescription":"Texas Instruments PCF8574ADWG4, I²C-bus I/O expander, 8 I/O, push-pull output, 100 kHz clock, 2.5V–6V supply, -40°C to 85°C, 16-SOIC, Tube.","salesMarkdown":"## I²C GPIO expander for mixed-voltage buses The PCF8574ADWG4: It runs on a supply from 2.5V to 6V, so it bridges 3.3V and 5V logic domains without a level shifter on the I²C lines. The 8 I/O pins are push-pull, each sourcing 1 mA and sinking 25 mA — enough to drive an LED directly or switch a small relay through a transistor. A dedicated interrupt output (INT) flags the host when an input changes state, saving polling cycles in the firmware. The 2.5V to 6V supply range covers both 3.3V and 5V systems. The I²C interface follows the supply rail, so a 3.3V-powered PCF8574ADWG4 presents 3.3V logic levels on SDA and SCL — no extra pull-up voltage divider needed. At 5V supply, the I/O pins swing rail-to-rail, which matches standard 5V microcontroller inputs. ## I²C bus speed and address configuration I²C interface runs at 100 kHz standard mode. The PCF8574A variant uses a different address block than the base PCF8574 — three address pins let you set one of eight addresses. POR ensures outputs default high after power-up. The wide-body variant provides better clearance for manual probing and rework compared to the narrow SOIC-16. For dual-sourcing resilience, the base PCF8574 (without the 'A' suffix) is pin-compatible but uses a different I²C address range — verify your firmware address map before substituting.","metaTitle":"PCF8574ADWG4 I²C GPIO Expander, 8 I/O, 2.5V–6V, 16-SOIC","metaDescription":"Texas Instruments PCF8574ADWG4 I²C-bus I/O expander with 8 push-pull I/O, 100 kHz clock, POR, interrupt output. 2.5V–6V supply, -40°C to 85°C. 16-SOIC.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Interface & Transceivers"],"specifications":{"Mfr":"Texas Instruments","Series":"-","Package":"Tube","Features":"POR","Interface":"I²C","Output Type":"Push-Pull","Mounting Type":"Surface Mount","Number of I/O":"8","Package / Case":"16-SOIC (0.295\\\", 7.50mm Width)","Clock Frequency":"100 kHz","lifecycle_stage":"eol_hot","Interrupt Output":"Yes","Voltage - Supply":"2.5V ~ 6V","Base Product Number":"PCF8574","Operating Temperature":"-40°C~85°C","Supplier Device Package":"16-SOIC","Current - Output Source/Sink":"1mA, 25mA"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/fb696dd34b280bb875ac664bb0ca53b4.pdf","sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/PCF8574ADWG4/alternatives.json"},"ai":{"faq":[{"question":"What is the difference between PCF8574ADWG4 and PCF8574?","answer":"Both are 8-bit I²C GPIO expanders with the same pinout and package options. The key difference is the I²C address range: the PCF8574A (this part) uses addresses 0x38–0x3F, while the base PCF8574 uses 0x20–0x27. The supply voltage, I/O current, and clock speed are identical."},{"question":"Can PCF8574ADWG4 be used with 5V microcontrollers?","answer":"Yes — the 2.5V to 6V supply range includes 5V, and the I/O pins swing rail-to-rail at 5V, matching standard 5V logic levels."},{"question":"Is PCF8574ADWG4 compatible with 3.3V logic?","answer":"Yes — when powered at 3.3V, the I²C interface and I/O pins operate at 3.3V levels, compatible with 3.3V microcontrollers without level translation."},{"question":"What is the address range of PCF8574A?","answer":"The PCF8574A uses I²C addresses 0x38 through 0x3F, selectable via the three address pins."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/texas-instruments/PCF8574ADWG4","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/texas-instruments/PCF8574ADWG4 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:49:49.435Z","lastPublished":"2026-08-11T15:49:49.435Z","indexable":true}}